BG61755B1 - Method and device for wet dust arresting - Google Patents

Abstract

The method and the device are used in metallurgy, mechanicalengineering and other industial sectors for cleaning the air frommechanical pollutants. By the method the dusty air gets through awater layer and labyrinth chambers (made of meshing) havingproportionally reducing hole sizes. As a result, the water-airmixture is being multiplicationally and continuously broken andthe wetted dust particles are gradually separated in the form offalling dirty rain. The device consists of a housing (1), settlingdevice (2) and cylindrical chambers (4) vertically positioned andopen in their lower part to the housing (1). The dusty air is fedthrough delivery tubes (9) suitably perforated in their lower endand across a system of mesh-type layers (5, 6, 7 & 8) forminglabyrinth chambers. The wetted mechanical pollutants (3) settle onthe bottom, and the clean air is separated through an outletchamber (13). In this way the followinf five zones of specificfunctional significance are formed in the process of air cleaningwithin the housing (1) volume: water mass zone; water-air zoneincluding a foamy (22) and precipitation (23) volume; generallabyrinth zone; zone for cleaned air and transitory zone. The dustarrestor is periodically charged with pure water across pipeline(18) The polluted water is periodically drained across shutter(16).

Description

Technical field

The invention relates to a method and device for wet dusting, which can be used in the metallurgy, mechanical engineering and other industries for the purification of air from metal and other mechanical pollutants.

BACKGROUND OF THE INVENTION

There is a method of wet dusting described in BC 18010, in which the liquid and the polluted air are subjected to vibration, resulting in the liquid being raised to a higher level. The device carrying out the method has at its upper part a vibrator with a vibrating tube connected thereto, which is immersed with its other end in the dust-collecting liquid. The vibrating tube is connected by an elastic connection to a clean air separation tube, and a perforated cone (1) is mounted at the lower end of the vibrating tube.

The disadvantage of the method and the device that implements it is that it consumes extra energy to create vibrations. In addition, vibrations create additional noise and can cause critical oscillation frequencies in the system as a whole, which in turn can lead to its rapid destruction.

A wet jet duct with internal circulation of the liquid is known, protected by BO 28594. The liquid occupies a predetermined volume in a housing, at the top of which a coagulation unit with a spray nozzle is mounted. The coagulation unit consists of an inlet connected in series with a confuser and a curvilinear vortex, under which a chamber is formed, at the bottom of which are contacted vortex channels to which anti-pulse barriers are mounted, with separation profiles above and contact vortices. drip trap. Contact eddy channels consist of fixed and movable walls, fixed with hinged nodes to the anti-pulse barriers / 2 /.

With this known dust collector, it is necessary to adjust several parameters with the corresponding control elements, which quickly change their parameters. It is difficult to apply to the capture of heterogeneous particles, especially metal dust.

Known dust collector (3), consisting of a barrel housing, at the bottom of which is placed the flushing water with a fixed level. At a certain distance above the water level, a finely ribbed plastic goblet resembling a fish gill is mounted, which rotates at a high peripheral speed. The created vortex passing through the gills provides efficient and complete dust removal of fine particles.

This type of dust collector is highly efficient for domestic use but is not suitable for industrial purposes, because when dusts with solids are absorbed and the saturation is increased, the finned plastic watch is worn out intensively, which is caused by its inefficiency.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a method of wet dust extraction and a device for its implementation with increased reliability and efficiency, versatile in the type and size of mechanical pollutants, simplified regulation and maintenance, with a high degree of air purification.

The problem is solved by a wet-dust method in which the dusty air is blown into water at a certain depth in a closed loop, with heavier particles settling. According to the invention, the entrained air is blown into partially localized volumes of water, at the upper end of which are maze chambers formed by mesh layers superimposed over one another, with proportionally decreasing mesh sizes, resulting in a multiplicity of continuous tearing of the water. the air mixture resulting in the separation of wetted dust particles at different stages in the water and water-air layers and in the maze chambers, depending on their size and mass from the carrier air ear leaving the area of the maze chambers. The two wetted dust particles, under the action of the peripheral part of the fluidized bed, coagulate in progressively rising dirt droplets downwards and in the form of "dirty rain" fall into the volume with calm sediment water.

The method according to the invention is carried out with a wet-dusting device, comprising a housing shaped like a closed vessel, the volume of which comprises its constituent elements. A sedimentation device is installed at the bottom of the housing. According to the invention, vertical cylindrical chambers are arranged symmetrically above the precipitating device at a certain height, parallel to each other and to the housing. Each of the cylindrical chambers has an open lower end to the lower part of the housing, and its upper end is embedded in a mesh layer with a certain size of openings. Above this mesh layer, other mesh layers are installed, each of which has proportionally decreasing apertures in the vertical direction relative to the previous layer. The mesh layers thus form labyrinthine chambers. At the axis of the cylindrical chambers, through all the mesh layers (labyrinth chambers), fixed discharge tubes with a closed lower end are fixed and at a certain distance perforated along their entire periphery with a certain diameter of openings. At their upper ends, the discharge pipes are connected by a common expansion chamber, which is fixedly sealed in the central upper part of the housing and sealed against it. The expansion chamber is connected to air ducts for dusty air. In the upper part of the housing, outside it, there is a centrally mounted fixed outlet chamber connected to the internal volume of the housing through a central pipeline. The volume of the wet-dust device to a certain level is filled with water.

An advantage of the wet dust collector according to the invention is the increased reliability of operation over a longer period of operation without cleaning and maintaining a high degree of air purification. Another advantage is the ability to clean both highly polluted industrial air, including metallic dust contaminated air, and air with particulate and rare mechanical pollutants, making it also suitable for air filtration in rooms with high requirements for air pollution. its purity. The wet powder method and apparatus according to the invention allow for a simplified control of the process, which, once the water level has been established, is practically self-regulating, with the labyrinthine zones being continuously cleaned from the continuously generated fluidized bed. An important advantage of a wet dust collector is its increased durability and simplified maintenance, with its servicing operations (maintaining the water level, replacing and refilling it, cleaning the sludge, etc.) to be automated and integrated into monitoring systems.

Description of the attached figures

Figure 1 is a schematic exemplary longitudinal section view of the wet dust collector according to the invention:

Figure 2 is a schematic sectional view of a wet dust collector explaining the cleaning principle.

Examples of carrying out the invention

According to the invention, the wet-dusting device consists of a housing 1 shaped like a closed vessel, the volume of which comprises its constituent elements. At the bottom of the housing 1 there is a settling device 2 of mechanical contaminants 3. Above the settling device 2, the ends of cylindrical chambers 4, which are parallel to each other and to the housing 1 in the vertical direction, are placed at the same distance as each other. as well as to the housing 1. The lower end of each cylindrical chamber 4 is open to the lower part of the housing 1 and its upper end is embedded at a depth "D" in a mesh layer 5 with a certain size of openings. Above the mesh layer 5, other mesh layers 6, 7 and 8 are fixed fixedly to the housing 1, with in each upward direction each layer having proportionally decreasing apertures relative to the previous one. In this way, the openings of the mesh layers 5, 6, 7 and 8 form labyrinthine chambers that are connected in series. Along the axis of

I cylindrical chambers 4, through all the mesh layers (labyrinth chambers) 5, 6, 7 and 8 and through the air-air and water layers fixed discharge tubes 9, clogged at the lower end and at a certain distance from it perforated throughout peripherals with a defined diameter of the openings, and at their upper ends are connected by a common expansion chamber 10, which is fixedly sealed in the central upper part of the housing 1 and sealed thereto.

The expansion chamber 10 is connected to air ducts 11 for dusty air 12. Above the housing 1 centrally thereto is a fixed outlet chamber 13 connected to the internal volume of the housing 1 through a central pipeline 14.

The volume of the dust collecting device to a certain level is filled with water 15 with the thickness of the water layer "a".

At the base of the housing 1 is installed a slide 16 for cleaning of the deposited mechanical contaminants 3.

In the central part of the housing 1 on its exterior, a level indicator 17 is connected to the workplace, connected to a clean water pipeline 18, an air pressure valve 19, the valve 19 being connected to that part of the volume of the housing 1 which is located between the mesh layer 5 and the upper water level 15.

In this way, five zones of defined functional importance are formed in the volume of the housing 1:

(a) a zone of water mass in which active water volumes 20 are formed through the cylindrical chambers 4 and absorbent water volumes 21 are formed in the water space around the cylindrical chambers 4 and the walls of the housing 1;

(b) a water-air zone in which there are two types of volumes: between the mesh layer 5 and the upper water level 15 in the spaces of the cylindrical chambers 4, a blowing foam volume 22; between the mesh layer 5 and the upper water level 15 around the cylindrical chambers 4 and the walls of the housing 1 are formed volumes 23;

(c) the volume of the common labyrinth area;

(d) volume of clean air;

(e) a transition zone formed by the depth of penetration of the cylindrical chambers 4 into the mesh layer 5.

The process of the invention is as follows.

Through the clean water pipeline 18 and level 5, clean water 15 with the thickness of the water layer "a" is charged.

The ducted air 12 is supplied through the ducts 11, which is distributed from the expansion chamber 10 into the discharge pipes 10 and enters the cylindrical chambers 4 in the form of jets of air bubbles created by the perforated openings, where contaminated air is contaminated with contaminated air. the coarsest dust particles15 qi that settle at the bottom.

The remaining semi-purified air (blisters) mixed with water droplets forms a foam which is lifted and forced upward in volumes 22 and passed into the transition zone (e), where a process of directed and multiplicated tearing begins (around the discharge tubes 9). of the water-air mixture (foam) from the bottom up to the full wetting of the dust particles, with the clean air entering the volume of zone (d) and through the pipeline 14 and the outlet chamber 13 into the atmosphere. At the same time, the wetted particles coagulate from smaller to larger droplets from top to bottom and, in the form of “dirty rain, fall through rainfall 23 in the area of the water mass (a), where one part of them precipitates and the other -the fine part re-engages in the boiling process and undergoes the same wetting and separation steps as described above.

In general, the process resembles the fountain shown in FIG. 2, on which the middle column ejects the continuously bursting bubbles upwards into the fresh air, and the wetted particles are reflected and pushed aside and downward from the labyrinth chambers and in the form of "dirty rain" enter the water volume for sedimentation.

This process continues until the permissible functional contamination of the water.

Periodically, the contaminated water 15 is drained through the valve 16 together with the precipitated mechanical contaminants 3, before which it is broken down to make it easier to flow.

Washing of the wet dust extraction device enters clean water through the pipeline 18 and detergents can be added up to 20.

Charging takes place through the same pipeline 18 to a predetermined technological level "a", which is monitored and maintained continuously through the level indicator 17.

The qualitative dynamic parameters of the process are additionally controlled by the air pressure valve 19.

Claims

Claims (4)

1. A method of wet dusting involving the interaction of an air stream contaminated with mechanical particles blown into water at a certain depth in a closed loop, the heavier particles precipitating at the bottom, characterized in that the dusty air (12) is blown at a certain depth in partially localized volumes of water from the total volume of water, whereby the water level in these volumes rises and transforms into a "boiling" water-air mixture, which is pumped and filtered into labyrinth chambers with proportionally decreasing openings in the vertical This is where the water-air mixture (foam) is finally self-purifying, breaking down to the full wetting of the dust particles, and purified air exits the top layer of the labyrinth chambers. 2. A wet-dusting method according to claim 1, characterized in that the breaking of the water-air mixture becomes up and down "umbrella" in the labyrinth chambers, whereby wetted particles of different stage and height are pushed aside along the periphery of the central flow depending on their volume and mass, thus the incoming wetted particles coagulate from top to bottom in continuously increasing dirty droplets, which in the form of "dirty rain" fall into the calm volume of water and settle. 3. The wet-dusting method according to claims 1 and 2, characterized in that the entire filtration and self-cleaning process in the labyrinth chambers is controlled by maintaining a certain water level at a height of "a". 4. The wet dust collecting device performing the method according to claims 1, 2 and 3 consists of a housing (1) shaped as a closed vessel filled with water (15) with a thickness of the water layer "a" at the bottom of which a sedimentation device (2) of mechanical contaminants (3) is installed, characterized in that vertical cylindrical chambers (4) which are parallel to the housing (1) and are arranged symmetrically above the sedimentation device (2) at a certain height. each with an open lower end and its upper end embedded in a mesh layer (5) distance "e" from the beginning of the mesh layer (5) over which other mesh layers (6, 7 and 8) are fixed to the housing (1), each of which in an upward direction has proportionally decreasing apertures relative to the previous one, forming labyrinth chambers connected in series and cylindrical chambers (4) in series, through the mesh layers (labyrinth chambers) (5, 6, 7 and 8) fixed discharge tubes (9), each with a closed bottom edge and perforated at a certain distance from it all over its periphery opened with a defined diameter and at its upper end the discharge tubes (9) are connected by a common expansion chamber (10), fixed in the central upper part of the housing (1) and sealed thereto, connected to air ducts (11) for dusty air (12). ), and a fixed outlet chamber (13) is connected above the housing (1) connected to the internal volume of the housing (1) through a central pipeline (14). Attachment: 2 figures